Wilhelm schmidt



(No Model.)

YW. SCHMIDT'. BUILBR.

.Patented Feb. 26, 1895'. Y

Inval/ffm MM2/M r perheater.

NiTED STATES PATENT OFFICE.

V-ILHELM SCHMIDT, OF WILHELMSHHE, NEAR CASSEL, GERMANY.

BOILER.

SPECIFICATION forming part of Letters Patent No. 534,673, dated February 2G, 1895.

Application filed November 17, 1 894. Serial No. 529,149. (No model.)

To all whom it may con/cern:

Be it known that I, WILHELM SCHMIDT, a subject of the King of Prussia, German Emperor, and a resident of Wilhelmshhe, near Cassel, in the Province of Hesse-Nassau, German Empire, have invented certain new and useful Improvements in Boilers, of which the following is an exact specification.

This invention refers -to steam-boilers, in which the boilerproper is combined with a su- My improvements in steamboil ers of thatkind relate to the combination with said boiler and superheater, of a feed-water heater, and of a regulator for the furnacegases.

The purposes of myimprovement are, first to control the degree of superheating by means of said regulator as well as by means of said' feed-water heater; second, to prevent the super-heater from being subjected to the furnace gases before steam'can flow through the same; and, third, to exhaust the f u rn ace-gases to the highest possible degree, as will all be more fully described hereinafter.

' In order to make my invention more clear, I refer to the accompanying drawings, in which similar letters refer to similar parts throughout the different views, and in which- Figure 1V shows a vertical section through a steam-boiler provided with a superheater, a feed-water heater and a regulator according to my invention. Fig. 2 shows a slightly modified form of construction.

, Referring to Fig. 1, a designates the boiler proper; b, the furnace; c, the passage for the furnacegases; d, a flue arranged centrally above passage c, and e a casingheld by boiler a.

The superheaterf which consists of a column of dat horizontal coils is arranged within the annular space between flue d and casing e, and communicates with boiler ahy the bent pipef. The steam thus flows through the coils f in a direction equal to that of the furnace, so that the wet steam on being acted on by the hottest gases of the furnace is first dried, and is thereafter superheated. The superheated steam escapes at f2.

The feed-water heater g consists likewise of a column of flat horizontal coils, and is arranged above the superheater within the annular space between tube dand casing e. The feed-water enters the coils g at the upper end .g2 of the latter, and Hows to the boiler a through the connecting-pipe g5. It will be seen, that the feed-water, contrary to the steam, `flows in a direction opposite to that of the furnace gases. The latter are thus acting first on that part of the feedwater, which has already been heated, while the cold water is subjected to those gases which are nearly Wholly exhausted.

A small space is left between the superheater' and the feed-water heater and at that place the tube d is provided with a number of apertures d. Said apertures may be closed by a circular slide h which is connected with a lever 1J by means of a rod lo. The latter has a collar kby means of which may be raised the lid Z that is closing the upper end of flue d. It will be seen, that lid Zcan be raised only after the apertures d have been freed from slide h. This a'rrangment now works as follows: Suppose that all parts be in the position shown in the drawings, and the boiler be fully at work, the steam flowing through the superheater will be dried and superheated by the furnace-gases that pass through the annular space between flue d and casing e. The furnace-gases are hindered from escaping through fine d directly to the chimney m, as lid Z as well as the apertures d are closed lf now from any cause the superheating of the steam becomes too strong, the slide h is raised by means of lever t' so that the apertures d become free of said slide. The furnace gases instead of passing through the space containing the superheater will then pass through the lower half of liue d and will flow from thence through the apertures d to and through the space containing the feed water heater, so that the heating of the feed water is increased, the superheating of the steam however decreased. As a matter of course, the su perheater need not wholly be deprived of the action of the heat, but only as much as necessary to reducethe superheating to its normal degree. The slide h therefore is raised only as little as necessary to obtain that result. It will be seen that the action ofthe furnace gases upon the superheater and the feed water heater may be regulated in any required degree by correspondingly adjusting the said slide h. If the furnace gases shall be hindered to act even on the feed water, lever IOO 'i is raised still more, so that lid Z is lifted by means of the collar k or rod 7c. Nearly the whole amount of the furnace gases is passing then straightway through the central iue CZ and up into the chimney m, so that during that time there is practically neither a heating of the feed water nor a superheating of the steam. It will be seen, that also in this case the lid Z may be raised but very little at first, so that part of the furnace-gases is escaping directly into the chimney, and part of the same on the by-way through the space containing the feed water heater.

lVhen the fuel in the furnace has'anew Vbeen kindled,y the position of the lid is that as last described, i. e., the lid is fully raised so that the gases coming from furnaceb may freely escape into the chimney without being able to act on the two columns of the pipesf and g. This is of great importance, in that, as there is no steam, yet within the superheater, the latter is perfectly prevented from becoming glowing. As soon, however, as the tension of the steam has reached the required strength for the respective engine, communication (which has been interrupted up to then) between the boiler proper and the superheater is established, so that the latter becomes filled with steam and the lid Z and slide Zz are lowered down to the position shown in the drawings, when the whole apparatus will commence to work as described.

In some cases, I prefer to combine with the feed 4water heater that is arranged above the superheater another feed-water heater, which I arrange below the snperheater, il. e., between the superheater and the boiler proper, as shown in Fig. 2. This second superheater g is connected with the first by the pipe g3 and with the boiler a by the pipe g4. This connection is made in such a manner, that the feed-water flowing through the second heater moves in a direction equal to that of the furnace-gases, while the water [iowing through the upper feed-water heater moves in a, direction 'opposite to the furnace gases just as described with regard to Fig. l. Slide his in this mode of construction arranged not within the central flue CZ but below the same in such a manner, that, if in normal position, slide ZL prevents the furnace gases from acting on the lower superheater g', but allows the same freely to act upon the two other columns or coilsf and g. If now from any cause, a diminution ofthe superheating becomes necessary, slide ZL is more or less raised by means of rod Zt and lever t', so that a part of the furnace gases, or the whole of the same, is compelled to flow through the space containing the lower feed water heater. The heat of the gases acting on the superheater is thus reduced as is also the degree of superheating. If the firegases are to pass directly into the chimney, lid Z is lifted by collar 7e of rod 71:, when the three columns g', f, and g will be practically free from any influence of the hot gases.

heater, two superposed valves adapted to co- Y operate for that purpose with said flue, substantially as described.

3. In a steam-boiler, the combination with a tubulous snperheater, of a tubulous feedwater heater a flue adapted to divert the furnace-gases from their way around the superheater, two superposed valves adapted to cooperate for that purpose with said flue, the upper of said valves being adapted to close the iue, the lower to be operated independent of the upper, substantially as described.

4. In a steam-boiler, the combination with a tubulous snperheater, of a tubulous feedwater heater a flue adapted to divert the furnace-gases from their Way around the superheater, two superposed valves adapted to cooperate for that purpose with said flue, the lower of said valves being connected to a rod extending loosely through the upper valve, said rod having a collar adapted to act on said upper valve after the lower one has been acted on, substantially as described.

5. In a steam-boiler, the combination with a tubulous snperheater, of a tubulous feedwater heater a flue adapted to divert the furnace-gases from their way around the superheater, two superposed valves adapted to cooperate for that purpose with said flue, one part of said feed-Water heater being arranged above the snperheater, the other below the same, substantially as described.

6. In a steam-boiler, the combination with a tubulous snperheater, of a tubulous feedwater heater, a flue ladapted to divert the furnace-gases from their way around the superheater, two superposed valves adapted to cooperate for that purpose with said fiue, one part of said feed-water heater being arranged above the snperheater, the other below the same, the lower end of the lower feed-water heater being connected with the lOwer end of the upper feed-water heater, the upper end of the lower feed-water-heater being connected with the boiler, substantially as described.

In testimony whereof I have signed this specification in the presence of two subscribing witnesses.

WILHELM SCHMIDT. Witnesses:

CHAs. H. DAY, WM. HAUPT.

IOC.

IIO 

